React components and DOM utilities for the snap system:
- SnapGuideOverlay: pre-allocated div pool (6 guides + 4 spacing)
for ref-driven guide line rendering during drag
- SnapToolbar: magnet/grid toggle with S/G keyboard shortcuts,
right-click grid popover for spacing config
- GridOverlay: CSS repeating-linear-gradient grid, GPU composited
- snapTargetCollection: walks iframe DOM tree to collect visible
elements as snap targets, cross-iframe safe (nodeType check)
Miguel Ángel
f8bf039a09
